A flexible continuum and ERCP procedure lifting forceps device and minimally invasive surgery robot

Abstract

The present application relates to a kind of flexible continuum and ERCP surgery with lifting forceps device and minimally invasive surgery robot, the flexible continuum includes multiple rigid segments, wherein: any two adjacent rigid segments are connected to be arranged in spring-like helical segment;Multiple the helical segment includes multiple clockwise helical segment and multiple counterclockwise helical segment, the clockwise helical segment and counterclockwise helical segment are alternately arranged;The hollow interior of each helical segment is matched with the spherical pair discrete joint connected with two adjacent rigid segments, the spherical pair discrete joint is made of multiple ball-and-socket joints, which are connected in the form of spherical contact between each other, and the helical segment is wound on multiple ball-and-socket joints respectively.The flexible continuum of the present application compared with the distal flexible joint of conventional minimally invasive surgery robot can effectively reduce and prevent the axial compression condition that has greater influence on end positioning accuracy in bending deformation, and has better bending performance and load capacity.

Description

Technical Field

[0001] This invention relates to the field of medical devices, specifically to a flexible continuum, a forceps lifter for ERCP surgery, and a minimally invasive surgical robot. Background Technology

[0002] Robot-assisted ERCP (endoscopic retrograde cholangiopancreatography) is currently recognized as the gold standard for diagnosing pancreatobiliary diseases due to its advantages over traditional open surgery, including less trauma, shorter operation time, higher safety, and faster postoperative recovery. However, because ERCP is performed deep within the digestive system, it is more challenging than other gastrointestinal surgeries using flexible endoscopy techniques, resulting in a longer learning curve for surgeons. This limitation manifests in the following two aspects: (1) The distal flexible joints of ERCP surgical robots mainly adopt continuum structures. Researchers at home and abroad have conducted extensive research on the configuration of continuums. According to their configuration, continuums can be divided into discrete joint continuum structures and continuous continuum structures. Among them, discrete joint continuum structures have advantages such as high stiffness, high load capacity, and low processing difficulty. However, due to the discrete design of the joints, their constant curvature characteristics and compliance are poor, and the accuracy of motion is greatly affected by the processing and assembly accuracy and the friction between the kinematic pairs. Continuous continuum structures have advantages of good compliance and constant curvature characteristics due to their continuous and complete structure. However, their stiffness is low, making it difficult to withstand large loads. Furthermore, axial contraction will occur during bending deformation, leading to difficulties in precise control.

[0003] Currently, there are few continuum robots that can be used to diagnose and treat diseases of the pancreas and biliary region. Moreover, most continuum structures cannot simultaneously possess good flexibility and high load-bearing capacity, which may lead to complications such as perforation, bleeding, and pancreatitis during endoscopic intervention, posing a certain threat to the patient's life.

[0004] (2) The main challenges of ERCP surgery occur in the second stage of inserting the endoscope into the descending duodenum and in the third stage of inserting the guidewire catheter through the papilla. These challenges stem from two main factors: firstly, the endoscope tip lacks flexibility and sufficient load-bearing capacity; secondly, the commercially available endoscope tip lifters used in ERCP have limitations. Firstly, the lifters adjust the insertion angle using forceps, possessing only a single degree of freedom, resulting in limited motion precision. Secondly, the complex structure of the lifters makes cleaning and disinfection difficult, potentially leading to exogenous infections. Therefore, it is necessary to develop a continuous robotic system with a multi-degree-of-freedom lifter at the endoscope tip to improve surgical efficiency, reduce surgical difficulty, and decrease surgical risks and the possibility of secondary injury. Summary of the Invention

[0005] Based on the aforementioned defects and shortcomings of existing ERCP surgical robots, one of the objectives of this invention is to provide a flexible continuum with good bending deformation performance, as well as high resistance to axial compression and load capacity. When this flexible continuum is applied to the distal end of an ERCP surgical robot, it can effectively improve the control precision of the distal joint, thereby reducing the difficulty and risk of surgery.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a flexible continuum comprising multiple rigid segments, wherein: A spring-shaped helical segment connects any two adjacent rigid segments. The plurality of helical segments include a plurality of clockwise helical segments and a plurality of counterclockwise helical segments, wherein the clockwise and counterclockwise helical segments are arranged alternately; Each of the spiral segments has a spherical discrete joint inside its hollow interior that connects to two adjacent rigid segments. The spherical discrete joint is composed of multiple ball-and-socket joints that are connected to each other in a spherical contact manner. The spiral segment is wound around the multiple ball-and-socket joints.

[0007] Furthermore, the ball-and-socket joint includes a concave spherical surface and a joint body. The concave spherical surface is formed on the joint body and defines an opening on the joint body. The joint body is provided with a convex spherical surface. Between multiple ball-and-socket joints, the convex spherical surface of the previous ball-and-socket joint and the concave spherical surface of the next ball-and-socket joint are connected by a curved surface contact.

[0008] Preferably, the number of clockwise spiral segments is the same as the number of counterclockwise spiral segments, and the number of spring coils and pitch in the clockwise spiral segments are the same as the number of spring coils and pitch in the counterclockwise spiral segments.

[0009] Preferably, the flexible continuum can be integrally formed using 3D printing technology.

[0010] The present invention also provides a forceps lifter for ERCP surgery, connected to one end of the aforementioned flexible continuum. The forceps lifter can change the lifting angle of the catheter or guidewire used in minimally invasive surgery, and includes an inner shell and an inner slider; wherein: The inner slider is embedded in the inner shell and can move back and forth relative to the inner shell under the action of external force pushing and pulling; The inner shell is equipped with a first roller, and the inner slider is equipped with a second roller. The central axes of the first roller and the second roller are parallel to each other and intersect the central axis of the inner shell at a point perpendicular to each other. One end of the catheter or guidewire contacts the lower part of the second roller, and the other end is led through to abut against the upper part of the first roller.

[0011] Preferably, the lifting clamp further includes a housing, with an inner housing embedded within the housing and rotatably connected to it; the inner slider can drive the inner housing to rotate relative to the housing under the action of external force.

[0012] Preferably, a flexible steel wire shaft is fixed on the inner slider, and the flexible steel wire shaft is led through the central hole inside the flexible continuum to be connected to the rotary drive device. The rotary drive device includes a rotary drive motor, which is connected to a first ball screw. A first guide rail slider is threaded onto the first ball screw and is slidably mounted on a linear guide rail. The flexible steel wire shaft is connected to the first guide rail slider.

[0013] Based on the aforementioned flexible continuum and forceps lifter, the present invention also provides a minimally invasive surgical robot, wherein: the other end of the flexible continuum is connected to a proximal drive device, and at least four drive wires connecting each joint are evenly distributed along the circumferential direction on the flexible continuum, and the at least four drive wires are paired up, and each pair of drive wires can control the flexible continuum to achieve bending motion in one direction under the drive of the proximal drive device.

[0014] Furthermore, the proximal drive device includes a mounting frame, at least two sets of wire drive components, and at least two drive motors; wherein: At least two sets of wire drive components are rotatably mounted on the mounting frame; The wire driving component includes two wire winding wheels and a drive motor connecting shaft; of the two wire winding wheels, one is provided with a forward thread section and the other is provided with a reverse thread section; the two wire winding wheels are respectively fixed to the drive motor connecting shaft by set screws, and the drive motor connecting shaft is driven to rotate by the corresponding drive motor. At least two sets of drive wires are wound on two sets of wire drive components, and the two drive wires in each set are wound on a drive wire winding wheel with a forward thread section and a drive wire winding wheel with a reverse thread section, respectively.

[0015] Preferably, the proximal drive device is mounted on the integral feed drive module, which includes a module frame, a feed drive motor, and a second ball screw; wherein: The module frame is equipped with a linear guide rail, and a second guide rail slider is slidably mounted on the linear guide rail; The feed drive motor is connected to the second ball screw; The second ball screw is rotatably mounted on the module frame, and a front bracket is threaded onto the second ball screw. The front bracket is fixed to the second guide rail slider and connected to the mounting frame of the proximal drive device.

[0016] Compared with the prior art, the present invention has the following advantages and effects: 1. Compared with the distal flexible joints used in traditional minimally invasive surgical robots, the flexible continuum provided by this invention has the following advantages: (a) The continuum uses alternating spring-like helical segments and rigid segments as the main bending deformation areas; wherein: the arrangement of several rigid segments not only ensures the design requirements of the flexible joint working space, but also provides more support for the load capacity of the flexible joint; at the same time, several spring-like helical segments arranged between any two adjacent rigid segments can make the continuum have a longer fatigue life and better bending deformation repeatability. (b) In the multiple spring-like helical segments of the continuum, clockwise and counterclockwise helical segments are arranged alternately. This arrangement allows the continuum to absorb energy uniformly during bending deformation, resulting in uniform stress distribution, thereby reducing stress concentration and ensuring the uniformity of bending deformation. At the same time, the uniformity of bending deformation allows the curvature of the continuum to be almost constant, and the constant curvature assumption can be successfully applied to kinematic modeling to improve the motion control accuracy of the surgical robot's end joint. (c) Typically, flexible joints achieve bending deformation by tightening the drive wire. Therefore, when bending deformation occurs, an axial force is generated that compresses the flexible joint. In the flexible continuum described in this application, spherical discrete joints are connected and arranged inside the hollow parts of each spring-shaped helical segment. When an axial force is generated, the convex spherical surface in the spherical discrete joint will fit tightly against the concave cavity of the adjacent ball-and-socket joint, thereby effectively limiting the axial compression generated between the continuums during bending deformation. This results in higher end-positioning accuracy and stability of the flexible joint during the bending deformation process, and better bending performance.

[0017] 2. To verify the advantages of the flexible continuum described in this invention in terms of axial stiffness, load performance, and bending performance, this invention utilizes the SolidWorks Simulation module to conduct simulation experiments on a single-helix structure continuum, a clockwise and counterclockwise helix structure continuum, and the clockwise and counterclockwise helix structure continuum based on spherical contact described in this application, respectively, and analyzes their performance under the same axial load F. N The deformation under torque M and radial load Fr was investigated. Through simulation experiments, it was found that the flexible continuum proposed in this invention has better resistance to axial compression, torsion, and load-bearing capacity than the other two continuums.

[0018] 3. The present invention also provides a clamping device for use with the above-mentioned flexible continuum. The clamping device includes a shell, an inner shell, and an inner slider nested in sequence. The inner shell is rotatably connected to the outer shell, and the inner slider is slidably mounted on the inner shell. Rollers with their axes located on the clamping device axis are respectively provided on the inner shell and the inner slider. Specifically, by changing the center distance between the two rollers, the lifting angle of the guide tube or guidewire led out from the two rollers in the clamping device can be changed. By rotating the inner slider, the inner shell can be rotated, thereby achieving the deflection of the guide tube / guidewire insertion direction. In summary, the clamping device provided by the present invention, in addition to giving the guide tube / guidewire conventional feed degrees of freedom, also has guide tube lifting and deflection degrees of freedom, enabling more flexible multi-degree-of-freedom motion.

[0019] 4. The minimally invasive surgical robot of the present invention includes a flexible continuum, a forceps lifter disposed at the distal end of the flexible continuum, and a drive device disposed at the proximal end of the continuum. The drive device can drive the flexible continuum to perform bending motion of at least two degrees of freedom and feeding motion of the continuum and the forceps lifter as a whole. Among them, the spherical contact clockwise and counterclockwise helical structure continuum proposed in this application has better bending deformation performance, better resistance to axial compression, better constant curvature characteristics and better load capacity than other types of continuous flexible joints. When applied to ERCP surgery, it can effectively ensure the safety of endoscopic intervention and reduce surgical risks. At the same time, the multi-degree-of-freedom forceps lifter can effectively improve the accuracy of catheter or guidewire insertion, thereby improving surgical efficiency and reducing surgical difficulty. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a three-dimensional structural diagram of the flexible continuum described in an embodiment of the present invention.

[0022] Figure 2 This is a schematic cross-sectional view of the flexible continuum described in an embodiment of the present invention.

[0023] Figure 3 This is a schematic diagram of the spherical discrete joint in the flexible continuum described in an embodiment of the present invention.

[0024] Figure 4 This is a schematic diagram of the flexible continuum described in an embodiment of the present invention, in which a lifting clamp is provided at the distal joint.

[0025] Figure 5 This is a three-dimensional structural diagram of the lifting clamp described in an embodiment of the present invention.

[0026] Figure 6 This is an exploded view of the lifting clamp structure according to an embodiment of the present invention.

[0027] Figure 7 This is a schematic cross-sectional view of the lifting clamp described in an embodiment of the present invention.

[0028] Figure 8 This is a schematic diagram of the overall structure of the minimally invasive surgical robot described in an embodiment of the present invention.

[0029] Figure 9 This is a schematic diagram of the continuum assembly module structure in the minimally invasive surgical robot described in an embodiment of the present invention.

[0030] Figure 10 This is an exploded view of the wire drive module structure in the proximal drive device of the minimally invasive surgical robot described in an embodiment of the present invention.

[0031] Figure 11 This is an exploded view of the structure of the wire driving component in the wire driving module according to an embodiment of the present invention.

[0032] Figure 12 This is a schematic diagram of the rotation drive module structure according to an embodiment of the present invention.

[0033] Figure 13 This is a schematic diagram of the overall feed drive module structure in the proximal drive device described in an embodiment of the present invention.

[0034] Figure 14 This is a comparative schematic diagram of the single-helix structure continuum, the clockwise and counterclockwise helix structure continuum, and the spherical contact clockwise and counterclockwise helix structure continuum in Embodiment 7 of the present invention.

[0035] Figure 15 A diagram of the experimental setup used to verify the relevant properties of the flexible continuum described in this invention.

[0036] Labeling Explanation: 1. Flexible Continuum; 11. Clockwise Helical Segment; 12. Counterclockwise Helical Segment; 13. Spherical Discrete Joint; 131. Ball-and-House Joint; 132. Concave Spherical Surface; 133. Convex Spherical Surface; 134. Annular Edge; 14. Rigid Body; 15. Distal Joint; 16. Proximal Joint; 2. Lifting Clamp; 21. Outer Shell; 22. Inner Shell; 221. First Roller Mounting Part; 222. First Roller; 223. Inclined Structure; 23. Connecting Bearing; 24. Inner Slider; 241. Second Roller Mounting Part; 242. Second Roller; 3. Proximal Drive Device; 31. Mounting Frame; 311. Frame Top Plate; 312. Frame Bottom Plate; 313. Frame Side Plate; 32. Wire Drive Component; 321. Drive Motor Connecting Shaft; 322. Drive Wire Winding Wheel; 323. Bearing; 3 3. Drive motor; 34. Guide short column; 4. Continuous body assembly module; 41. Continuous body assembly frame; 42. Continuous body connecting seat; 43. Guide wire sheath; 44. Guide wire sheath connecting plate; 45. Drive wire guide column; 5. Overall feed drive module; 51. Module frame; 511. Module base plate; 512. Bearing bracket; 52. Linear guide rail; 53. Second guide rail slider; 54. Second ball screw; 55. Front bracket; 56. Rear bracket; 57. Feed drive motor; 6. Rotary drive device; 61. Bearing bracket; 62. Rotary drive motor; 63. First ball screw; 64. Linear guide rail; 65. First guide rail slider; 7. Guide tube; 8. Drive wire; 9. Power supply; 10. Servo motor driver group; 17. Motion controller; 18. Camera; 19. Computer control system. Detailed Implementation

[0037] The present invention will be further described in detail below with reference to the embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0038] Example 1: As Figures 1 to 3 As shown, this embodiment provides a flexible continuum comprising multiple rigid segments, wherein: like Figure 1 As shown, a spring-shaped spiral segment is connected between any two adjacent rigid segments. The multiple spiral segments include multiple clockwise spiral segments 11 and multiple counterclockwise spiral segments 12, and the clockwise spiral segments 11 and counterclockwise spiral segments 12 are arranged alternately. Furthermore, such as Figure 2 As shown, each of the spiral segments has a spherical discrete joint 13 that is connected to two adjacent rigid segments inside the hollow interior. like Figure 3 As shown, the spherical discrete joint 13 is composed of a plurality of ball-and-socket joints 131 connected to each other in a spherical contact manner, and the helical segment is wound around the plurality of ball-and-socket joints 131 respectively.

[0039] Specifically, in the flexible continuum described in Embodiment 1: like Figure 1 , 2 As shown, the rigid segment is columnar, and the multiple rigid segments are composed of several rigid bodies 14 and proximal joints 16 and distal joints 15 disposed at both ends of the continuum; wherein: the proximal joint 16 is used to connect with a device that drives the continuum to perform multi-degree-of-freedom motion, and the distal joint 15 is used to connect with a surgical instrument at the end.

[0040] like Figure 2 , 3 As shown, the ball-and-socket joint 131 includes a concave spherical surface 132 and a joint body; wherein: the concave spherical surface 132 is formed on the joint body and defines an opening on the joint body; the joint body is provided with a convex spherical surface 133; in this embodiment, multiple ball-and-socket joints 131 are connected to each other in a spherical contact manner, which means that the convex spherical surface 133 of the previous ball-and-socket joint and the concave spherical surface 132 of the next ball-and-socket joint are connected in a curved contact manner.

[0041] Furthermore, such as Figure 3 As shown, in the ball-and-socket joint 131 described in this embodiment: The convex spherical surface 133 may be configured in a generally hemispherical shape; the concave spherical surface 132 may be configured in a hemispherical concave cavity that matches the convex spherical surface. The concave spherical surface 132 and the convex spherical surface 133 are connected through each other. A central channel is formed between each interconnected ball-and-socket joint 131, which is connected to two adjacent rigid segments. The central channel can be used for the passage of surgical instruments such as endoscopes, catheters or guide wires for minimally invasive surgery, so as to facilitate the exploration of the surgical environment and surgical operations.

[0042] The joint body also includes an annular edge 134 for defining the opening, the convex spherical surface 133 is connected to the annular edge 134, and each of the spring-shaped helical segments is respectively wound and connected to multiple annular edges 134 of a plurality of ball-and-socket joints.

[0043] Furthermore, such as Figure 2 , 3 As shown, in the spherical discrete joint described in this embodiment, the number of ball-and-socket joints 131, the radii of the convex spherical surface 133 and the concave spherical surface 132, the distance between the centers of the convex and concave spherical surfaces, and the height and radius of the annular edge 134 should be adapted to the number of turns and pitch of the spring in the spring-like helical segment, so as to minimize the axial compression between the flexible joints during the bending deformation of the continuum and the impact on the positioning accuracy of the joint end.

[0044] Compared with existing discrete and continuous continuums, the flexible continuum proposed in this invention has better bending deformation performance, higher resistance to axial compression, better constant curvature characteristics, and better load-bearing capacity. The reasons are analyzed as follows: (1) In this embodiment, the flexible continuum adopts an alternating arrangement of spring-shaped helical segments and rigid segments; wherein: the setting of rigid segments ensures that the working space of the flexible joints in the continuum meets the design requirements and provides more support for the load capacity of the continuum; on the other hand, the helical structure that is alternately set with rigid segments also makes the continuum have a longer fatigue life and better bending deformation repeatability. (2) In the structural design, the alternating clockwise and counterclockwise spiral segments are used as the main bending deformation area of ​​the continuum. This arrangement allows the continuum to absorb energy evenly when it undergoes bending deformation under the action of the driving wire, resulting in uniform stress distribution and reducing stress concentration. At the same time, the uniformity of bending deformation makes the bending curvature of the continuum almost constant, which is beneficial to the accuracy of kinematic modeling. (3) Usually, flexible joints are bent by tightening the drive wire. Therefore, when bending deformation occurs, axial force will be generated to compress the flexible joint. In the flexible continuum described in this embodiment, multiple ball-and-socket joints that are connected to each other in a spherical contact manner are set in the hollow interior of each spring-shaped helical segment. When an axial force is generated, the convex spherical surface in the ball-and-socket joint will be pressed against the concave cavity of the adjacent ball-and-socket joint to limit the axial compression generated by the continuum during bending deformation, so that the end positioning accuracy and stability of the flexible continuum are better during the bending deformation process. At the same time, due to the characteristics of spherical contact, this setting method does not affect the overall bending deformation effect of the flexible joint.

[0045] Example 2: As Figures 1 to 2 As shown, in order to further improve the uniformity of bending deformation of the flexible continuum described in this invention, this embodiment, based on Embodiment 1, further defines the following: The number of clockwise spiral segments 11 is the same as the number of counterclockwise spiral segments 12, and the number of spring coils and pitch in the clockwise spiral segments 11 are the same as the number of spring coils and pitch in the counterclockwise spiral segments 12.

[0046] Specifically, such as Figure 1 As shown, in this embodiment, there are two clockwise spiral segments 11 and two counterclockwise spiral segments 12, and the number of spring coils in both the clockwise and counterclockwise spiral segments is 3.

[0047] Specifically, clockwise spiral segment 11 and counterclockwise spiral segment 12 are arranged in pairs as the main bending deformation areas of the flexible continuum. When the continuum bends and deforms, the paired clockwise and counterclockwise spiral segments with the same parameters can absorb energy more evenly, making the stress distribution more uniform, thereby further reducing the occurrence of stress concentration, and making the continuum have better compliance and constant curvature characteristics.

[0048] Furthermore, the flexible continuum described in Embodiments 1 and 2 of the present invention is an integrated design, with an outer diameter of 12 mm, an internal hollow channel diameter of 3.5 mm, and a total length of 100 mm. It can be manufactured using 3D printing technology and laser sintering of PA12 nylon material into an integrated form, which has the characteristics of easy processing and low manufacturing cost.

[0049] Example 3: As Figures 4 to 7 As shown, the present invention also provides a lifting clamp 2 that can be assembled onto the distal joint 15 of a flexible continuum, the lifting clamp 2 enabling the change of the lifting angle of the catheter 7 or guidewire used in robot-assisted ERCP surgery; wherein: like Figure 5 , 6 As shown in Figures 7 and 8, the lifting clamp 2 includes an inner shell 22 and an inner slider 24. The inner slider 24 is embedded inside the inner shell 22 and can move back and forth relative to the inner shell 22 under the action of external force. The inner shell 22 is equipped with a first roller 222, and the inner slider 24 is equipped with a second roller 242. The central axes of the first roller 222 and the second roller 242 are parallel to each other and intersect the central axis of the inner shell at a point perpendicular to each other. One end of the conduit 7 or guidewire contacts the lower part of the second roller 242, and the other end is led through to abut against the upper part of the first roller 222.

[0050] like Figure 7 As shown, the forceps lifter described in Embodiment 3 of the present invention can increase or decrease the lifting angle of the catheter 7 or guidewire used in minimally invasive surgery, thereby changing the insertion angle of the catheter 7 / guidewire during surgical operations. The working principle is as follows: (In this embodiment, the catheter is specifically used as an example) In the lifting clamp, the central axes of the first roller 222 and the second roller 242 are at the same height and intersect the central axis of the inner shell 22 of the lifting clamp at one point (point A and point B). When the cannulation operation is performed, one end of the cannula 7 contacts the lower part of the second roller 242, and the other end is led through to the upper part close to the first roller 222. At this time, under the action of external force pushing and pulling, the inner slider 24 and the inner shell 22 can be made to translate, thereby increasing or decreasing the distance between the two central axes of the first roller 222 and the second roller 242, thus changing the lifting angle θ of the guide tube 7.b Of which: when the distance between the two central axes increases, the lifting angle of the catheter decreases, and when the distance between the two central axes decreases, the lifting angle of the catheter 7 increases.

[0051] Furthermore, such as Figure 6 , 10 As shown in Figures 1 and 12, in this embodiment, the translational movement of the inner slider 24 can be achieved in the following manner: A flexible steel wire shaft (not shown in the attached figure) is fixed on the inner slider 24. The flexible steel wire shaft is led through the central channel inside the flexible continuum 1 and connected to the rotary drive device 6. The rotary drive device includes a rotary drive motor 62, which is connected to a first ball screw 63 rotatably mounted on a bearing bracket 61. A first guide rail slider 65 is threaded onto the first ball screw 63 and is slidably mounted on a linear guide rail 64. The flexible steel wire shaft is connected to the first guide rail slider 65. When the rotary drive motor 62 is started, the first ball screw 63 rotates, and the first guide rail slider 65 threaded onto the first ball screw 63 can move back and forth along the linear guide rail 64, thereby driving the flexible steel wire shaft to push and pull the inner slider 24, thereby changing the distance between the two central axes of the first roller 222 and the second roller 242, and thus changing the lifting angle of the guide tube.

[0052] Example 4: Figures 4 to 7 As shown, this embodiment, based on embodiment 3, provides another lifting forceps, which can drive the minimally invasive surgical catheter 7 to deflect, thereby changing the insertion direction of the catheter; specifically, the difference between the lifting forceps described in this embodiment and that in embodiment 3 is: The lifting clamp 2 also includes a housing 21, and an inner housing 22 is embedded in the housing 21 and rotatably connected to the housing 22; The inner slider 24 can drive the inner shell 22 to rotate relative to the outer shell 21 under the action of external force, thereby driving the guide tube 7 disposed between the first roller 222 and the second roller 242 to deflect.

[0053] Specifically, such as Figure 6 As shown in the figure, in the lifting clamp described in this embodiment, a steel wire flexible shaft (not shown in the figure) can be connected to one end of the inner slider 24. By manually twisting the steel wire flexible shaft, the inner slider can be driven to rotate, thereby driving the inner shell to rotate.

[0054] In addition, in the lifting clamps described in embodiments 3 and 4 of the present invention, the guide tube 7 can also be given conventional feed degrees of freedom by pushing and pulling the guide tube 7, that is, it can move forward or backward along the current direction.

[0055] Furthermore, in the lifting clamp described in Embodiment 4 of the present invention: (1) such as Figure 6As shown, the outer shell 21 has a hollow cylindrical structure, and the shell has a slot for easy insertion of catheters, guide wires or endoscopes; The inner shell 22 has a similar shape to the outer shell, including a hollow cylinder and an integrally formed arc-shaped surface; wherein: a first roller mounting part 221 is provided on the arc-shaped surface, the first roller 222 is mounted on the first roller mounting part 221 by a cylindrical pin, and the first roller mounting part 221 is rotatably connected to the outer shell 21 by a connecting bearing 23; The inner slider 24 has a cylindrical structure that matches the hollow cylinder of the inner shell 22. The end of the inner slider 24 is provided with a second roller mounting part 241, and the second roller 242 is fixed to the second roller mounting part 241 by a cylindrical pin.

[0056] (2) such as Figure 6 As shown, preferably, the inner shell 22 is provided with an inclined structure 223 located between the first roller 222 and the second roller 242. The conduit 7 passes through the inclined structure 223 to abut against the upper part of the first roller 222. The inclined structure 223 mainly serves a supporting and guiding function, facilitating the guidance of the conduit from the outer cylindrical surface of the second roller 242 to the outer cylindrical surface of the first roller 222. In this embodiment, there are no specific requirements for the slope of the inclined structure 223; it is sufficient to guide the conduit to the outer cylindrical surface of the first roller.

[0057] (3) such as Figure 6 As shown, a sliding pair is provided between the inner slider 24 and the inner shell 22; in one embodiment, two protrusions are symmetrically arranged on the hollow cylinder of the inner shell 22, and two grooves are symmetrically opened on the inner slider 24. The inner slider 24 and the inner shell 22 are slidably installed by the mutual cooperation of the protrusions and grooves, and can generate translational movement under the action of external force pushing and pulling.

[0058] In summary, the clamping device described in Embodiment 4 of the present invention, in addition to giving the catheter 7 or guidewire conventional feed degrees of freedom, also has catheter / guidewire lifting and deflection degrees of freedom, enabling more flexible multi-degree-of-freedom motion.

[0059] Example 5: Figure 2 , 8 As shown, based on the flexible continuum described in Examples 1 and 2 and the forceps lifter described in Examples 3 and 4, the present invention provides a minimally invasive surgical robot, including a flexible continuum 1. like Figure 8 As shown, the distal joint of the flexible continuum 1 is connected to the lifting clamp 2, and the proximal joint is connected to the proximal drive device 3. like Figure 2As shown, at least four drive wires 8 are evenly distributed along the circumferential direction on the flexible continuum 1, connecting each joint. The at least four drive wires 8 are in pairs, and each pair of drive wires can control the flexible continuum to achieve bending motion in one direction under the drive of the proximal drive device.

[0060] In this embodiment, when the number of driving wires 8 is set to 4, the proximal driving device 3 can drive the flexible continuum to perform two-degree-of-freedom bending motion.

[0061] Specifically, such as Figure 8 , 10 As shown in Figure 11, in this embodiment, the proximal drive device 3 includes a mounting frame 31, at least two sets of wire drive components 32, and at least two drive motors 33; wherein: At least two sets of wire drive components 32 are respectively mounted on the mounting frame 31 via bearings 323; like Figure 11 As shown, the wire driving component 32 includes two wire winding wheels 322 and a drive motor connecting shaft 321; of the two wire winding wheels 322, one is provided with a forward thread section and the other is provided with a reverse thread section. The two wire winding wheels are respectively fixed to the drive motor connecting shaft 321 by set screws. The drive motor connecting shaft 321 is driven to rotate by the corresponding drive motor 33. At least two sets of drive wires are wound on two sets of wire drive components 32, and the two drive wires in each set are wound on a drive wire winding wheel with a forward thread section and a drive wire winding wheel with a reverse thread section, respectively.

[0062] Furthermore, such as Figure 8 , 9 As shown in Figures 1 and 10, in the minimally invasive surgical robot described in this embodiment: (1) The flexible continuum 1 is connected to the proximal drive device 3 via a continuum assembly module 4, the continuum assembly module 4 including a continuum connecting seat 42 and a continuum assembly frame 41; wherein: like Figure 9 As shown, the continuous body connecting seat 42 is provided with multiple limiting grooves, and the proximal joint 16 of the flexible continuous body 1 is provided with multiple corresponding protrusions. The axial and circumferential positioning of the continuous body can be achieved by the mutual cooperation of the protrusions and grooves and the fixing with set screws, thereby reducing the systematic error during the installation process; The continuum assembly frame 41 is provided with a guide wire sheath 43, a guide wire sheath connecting plate 44, and a drive wire guide post 45. Multiple drive wires 8 are led out from the proximal joint of the continuum and pass through the guide wire sheath and the guide wire sheath connecting plate in sequence. Under the guidance of the drive wire guide post, they are connected to the drive wire winding wheel. The guide wire sheath 43 can reduce the friction between the drive wire and the assembly parts. The drive wire guide post 45 can arrange multiple drive wires in an orderly manner and prevent them from getting entangled.

[0063] (2) such as Figure 10 As shown, in the proximal drive device 3, the mounting frame 31 is composed of a frame top plate 311, a frame bottom plate 312, and two frame side plates 313; the frame top plate 311 and the frame bottom plate 312 are respectively provided with a plurality of guide short posts 34; in this embodiment, when there are four sets (8 wires) of drive wires, the number of guide short posts 34 is 8, 4 are connected to the frame top plate 311 and 4 are connected to the frame bottom plate 312, respectively, to guide the drive wires on the 8 drive wire winding wheels arranged in opposite directions in the four sets of wire drive components 32, and to prevent the drive wires from winding when the drive motor 33 is working and the flexible continuous body 1 is bent and deformed.

[0064] (3) such as Figure 11 As shown, in the wire driving component 32, the wire winding wheel 322 is provided with a spiral groove and a wire fixing hole. For two driving wires controlling a single degree of bending freedom, after being guided, they are wound in opposite winding directions within the spiral groove and fixed to the wire fixing hole at the end of the spiral groove. This arrangement can limit the movement of the driving wires during winding, preventing them from stacking together and causing increased friction, inaccurate wire length control, and other system errors. Simultaneously, due to the spiral direction of the driving wire spiral groove on the wire winding wheel 322 and the specific winding method of the driving wires, antagonistic movement of each group of two driving wires can be achieved, i.e., the effect of one wire increasing in length while the other decreases in length. In this embodiment, the proximal drive device can be equipped with up to four drive motors controlling wire length, realizing the control of eight driving wires.

[0065] (4) In the wire drive component 32, in order to adjust the preload of the drive wire, the top wire on the designated drive wire winding wheel 322 can be loosened so that it can rotate relative to the drive motor connecting shaft 321. By rotating the drive motor connecting shaft 321, the preload of the drive wire can be finely adjusted, thereby realizing the independent, fast and convenient adjustment of the preload of each drive wire.

[0066] (4) such as Figure 10 As shown, the rotary drive device 6 is mounted on the frame base plate 312 of the proximal drive device.

[0067] The minimally invasive surgical robot described in this embodiment can be applied to ERCP surgery. Its distal continuum has better bending deformation performance, better constant curvature characteristics and better load capacity. At the same time, the lifter set on the distal continuum allows the catheter to have not only conventional feed degrees of freedom, but also catheter lifting degrees of freedom and deflection degrees of freedom, enabling more flexible multi-degree-of-freedom movement.

[0068] Example 6: As Figure 8 , Figure 13 As shown, this embodiment provides another minimally invasive surgical robot, which differs from embodiment 5 in that: the proximal drive device 3 is mounted on the overall feed drive module 5, and the overall feed drive module 5 includes a module frame 51, a feed drive motor 57, and a second ball screw 54; wherein: The module frame 51 consists of a module base plate 511 and a bearing bracket 512 disposed on the module base plate 511. A linear guide rail 52 is provided on the module base plate 511, and a second guide rail slider 53 is slidably mounted on the linear guide rail 52. The feed drive motor 57 is connected to the second ball screw 54; The second ball screw 54 is rotatably mounted on the bearing bracket 512, and the second ball screw 54 is threadedly fitted with the front bracket 55. The front bracket 55 is fixed on the second guide rail slider 53 and connected to the mounting frame 31 of the proximal drive device.

[0069] Preferably, the overall feed drive module 5 described in this embodiment also includes a rear support 56, which is parallel to the front support 55 and is slidably mounted on the linear guide rail 52. This ensures that when the feed drive motor 57 starts, it smoothly drives the proximal drive device 3 to move back and forth along the linear guide rail 52.

[0070] In summary, the minimally invasive surgical robot provided in this embodiment can achieve at least 6 degrees of freedom of motion, including: at least two bending degrees of freedom of the distal flexible continuum, lifting degree of freedom + deflection degree of freedom + feed degree of freedom of the forceps catheter, and overall feed degree of freedom of the continuum robot; among which, the design of the distal flexible joint effectively reduces and prevents axial compression that has a significant impact on the positioning accuracy of the end effector during bending deformation, and has good compliance and load capacity; the forceps design can achieve 3 degrees of freedom of motion, which improves the flexibility of surgical operation compared with existing commercial single-degree-of-freedom forceps.

[0071] Example 7: Figure 14As shown, in order to verify the advantages of the flexible continuum described in Embodiments 1 and 2 of the present invention in terms of axial stiffness and bending performance, the present invention uses the SolidWorks Simulation module to simulate and analyze the deformation of a single-helix structure continuum, a clockwise and counterclockwise helix structure continuum, and a spherical contact clockwise and counterclockwise helix structure continuum (i.e., the flexible continuum provided by the present invention) under the same load.

[0072] Specifically, the three types of continuums are required to have identical dimensions, materials, elastic modulus, and Poisson's ratio, and the same axial load is applied to the distal ends of each continuum. F N Torque M and radial load F Using the nonlinear simulation option in the Simulation module, the deformation of the three flexible joints can be displayed intuitively, and the resultant displacement of the distal end of the three continuums under three different loads can be recorded.

[0073] Simulation experiments show that the flexible continuum (spherical contact clockwise and counterclockwise helical structure) provided by this invention, compared with the other two types of continuums, under the same axial load... F N Torque M and radial load F Under the action of r, the resultant displacement generated at the distal end is minimal; therefore, it is shown that the flexible continuum described in this invention has excellent performance in terms of resistance to axial compression, torsion, and radial load-bearing capacity.

[0074] Example 8: This example further verifies the performance indicators of the flexible continuum provided by the present invention through the following experiments; Specific experimental setup: such as Figure 15 As shown, the experimental setup mainly consists of a computer control system 19, a motion controller 17, a servo motor driver group 10, the minimally invasive surgical robot described in this invention, a camera 18, and a power supply 9; wherein: The computer control system 19 is used to send the required commands to the motion controller 17 and to receive feedback through an ADS-based communication method; The motion controller 17 sends commands to the servo motor driver group 10 via the Ethercat bus and controls the flexible continuum in the minimally invasive surgical robot to perform bending motion; Camera 18 is used to record the end position of the joint in real time during the bending process of the continuum joint.

[0075] The specific experiment is as follows: (1) The influence of axial compression on the positioning accuracy of the end of the flexible continuum described in this invention was verified and analyzed through kinematic accuracy experiments; The motion controller 17 and the servo motor driver group 10 send commands to the drive motor in the minimally invasive surgical robot to control its rotation. The motor's motion is set to point-to-point motion mode so that the motor rotates uniformly by the same angle after each command is sent.

[0076] After adjusting the flexible continuum to its initial zero-bending position, it is loaded until the bending deformation angle of the flexible joint exceeds 120°. At five positions with flexible joint deflection angles of 0°, 30°, 60°, 90°, and 120°, the end position of the flexible joint during bending is recorded by a camera in the experimental system. By calibrating the initial position and setting the scale, the coordinates of the end of the flexible continuum during deformation can be calculated.

[0077] The experiment shows that: The continuum described in this invention exhibits high end-positioning accuracy during bending deformation (axial compression has little impact on the end-positioning accuracy of the flexible joint), thereby giving it excellent constant curvature and bending performance, which is beneficial to the precision and efficiency of surgical operations.

[0078] (2) Load performance test To verify the load-bearing performance of the flexible continuum described in this invention during bending, this experiment applied a force of 1.2N to the distal end of the continuum when the bending angle was 30°, 60°, 90°, and 120°, and recorded the deformation of the flexible joint. The experimental results show that when the flexible continuum undergoes bending deformation, its stiffness is improved compared to the zero bending position. Within a certain range, the larger the bending angle, the smaller the deformation at the end and the stronger the load-bearing capacity.

[0079] Therefore, if a large output force is required during the operation, the continuum should be deformed at a certain angle to improve the stiffness of the flexible joint. In the experiment, applying a load to the end of the flexible joint did not cause instability, indicating that the flexible continuum described in this invention has sufficient stiffness. Furthermore, after the load was removed, the flexible joint maintained good shape curvature without plastic deformation, indicating that the flexible continuum described in this invention has good bending deformation repeatability.

[0080] Note: In this invention, the term "flexible joint" is synonymous with "flexible continuum".

[0081] Furthermore, it should be noted that the shapes and names of the parts and components described in the specific embodiments described in this specification may differ. All equivalent or simple variations made to the structure, features, and principles described in this patent concept are included within the protection scope of this patent. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to replace them, as long as they do not depart from the structure of this invention or exceed the scope defined in these claims, they should all fall within the protection scope of this invention.

Claims

1. A forceps lifter for ERCP surgery, connected to one end of a flexible continuum, characterized in that, The lifting forceps can change the lifting angle of the catheter or guidewire used in minimally invasive surgery, and includes an inner shell and an inner slider; wherein: The inner slider is embedded in the inner shell and can move back and forth relative to the inner shell under the action of external force pushing and pulling; The inner shell is equipped with a first roller, and the inner slider is equipped with a second roller. The central axes of the first roller and the second roller are parallel to each other and intersect the central axis of the inner shell at a point perpendicular to each other. One end of the catheter or guidewire contacts the lower part of the second roller, and the other end is led through to abut against the upper part of the first roller.

2. The lifting clamp according to claim 1, characterized in that, The lifting clamp also includes a housing, and an inner housing is embedded in the housing and rotatably connected to the housing; the inner slider can drive the inner housing to rotate relative to the housing under the action of external force.

3. The lifting clamp according to claim 2, characterized in that, A flexible steel wire shaft is fixed on the inner slider. The flexible steel wire shaft is led through the central hole of the flexible continuous body to connect with the rotary drive device. The rotary drive device includes a rotary drive motor, which is connected to a first ball screw. A first guide rail slider is threaded onto the first ball screw and is slidably mounted on a linear guide rail. The flexible steel wire shaft is connected to the first guide rail slider.

4. The lifting clamp according to claim 1 or 3, characterized in that, The flexible continuum comprises multiple rigid segments, wherein: A spring-shaped helical segment connects any two adjacent rigid segments. The plurality of spiral segments include a plurality of clockwise spiral segments and a plurality of counterclockwise spiral segments, wherein the clockwise spiral segments and the counterclockwise spiral segments are arranged alternately; Each of the spiral segments has a spherical discrete joint inside its hollow interior that connects to two adjacent rigid segments. The spherical discrete joint is composed of multiple ball-and-socket joints that are connected to each other in a spherical contact manner. The spiral segment is wound around the multiple ball-and-socket joints.

5. The lifting clamp according to claim 4, characterized in that, The ball-and-socket joint includes a concave spherical surface and a joint body. The concave spherical surface is formed on the joint body and defines an opening on the joint body. The joint body is provided with a convex spherical surface. Between multiple ball-and-socket joints, the convex spherical surface of the previous ball-and-socket joint and the concave spherical surface of the next ball-and-socket joint are connected by a curved surface contact.

6. The lifting clamp according to claim 5, characterized in that, The number of clockwise spiral segments is the same as the number of counterclockwise spiral segments, and the number of spring coils and pitch in the clockwise spiral segments are the same as the number of spring coils and pitch in the counterclockwise spiral segments.

7. The lifting clamp according to claim 6, characterized in that, The flexible continuum can be integrally formed using 3D printing technology.

8. A minimally invasive surgical robot, comprising the forceps lifter as described in any one of claims 1 to 7, characterized in that, The other end of the flexible continuum is connected to the proximal drive device, and at least four drive wires connecting each joint are evenly distributed along the circumferential direction on the flexible continuum. The at least four drive wires are in pairs, and each group of drive wires can control the flexible continuum to achieve bending motion in one direction under the drive of the proximal drive device.

9. The minimally invasive surgical robot according to claim 8, characterized in that, The proximal drive device includes a mounting frame, at least two sets of wire drive components, and at least two drive motors; wherein: At least two sets of wire drive components are rotatably mounted on the mounting frame; The wire driving component includes two wire winding wheels and a drive motor connecting shaft; of the two wire winding wheels, one is provided with a forward thread section and the other is provided with a reverse thread section; the two wire winding wheels are respectively fixed to the drive motor connecting shaft by set screws, and the drive motor connecting shaft is driven to rotate by the corresponding drive motor. At least two sets of drive wires are wound on two sets of wire drive components, and the two drive wires in each set are wound on a drive wire winding wheel with a forward thread section and a drive wire winding wheel with a reverse thread section, respectively.

10. The minimally invasive surgical robot according to claim 9, characterized in that, The proximal drive device is mounted on the overall feed drive module, which includes a module frame, a feed drive motor, and a second ball screw; wherein: The module frame is equipped with a linear guide rail, and a second guide rail slider is slidably mounted on the linear guide rail; The feed drive motor is connected to the second ball screw; The second ball screw is rotatably mounted on the module frame, and a front bracket is threaded onto the second ball screw. The front bracket is fixed to the second guide rail slider and connected to the mounting frame of the proximal drive device.

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